Engine cylinder



2 Sheets-Sheet '1.

F- o# CLEMENTs ENGINE CYLINDER May 22, 192s. 1,670,843

F. O. CLEMENTS ENGINE CYLINDER Filed Nov. 9. 1922 2 sheets-sheet 2 EJHELLAC l GRAPHITE .DE CCIE PASTE l' SAND [ZIE 175155515 MM. 7? 74M Patented May 22, 1928. A

. UNITED STATES PATENTQOFFICE.

FRANK 0. CLEMENTS, OF DAYTON, OHIO, ASSIGNOR TO GENERAL MOTORS RESEARCH I CORPORATION, OF DAYTON, OHIO, A CORPORATION DELAWARE.

ENGINE CYLINDER.

Application led November 9, 1922. Serial No. 599,933.

The present invention relates to internal combustion engine cylinders and, 1n 1ts preferred form relates particularly to cylindersv for air cooled engines.

Among the objects of the invention is a cylinder which is easier and more economical to Aproduce and at the same time more efiicicnt thanthose heretofore known.

Another object' is a cylinderfabrica'ted of parts which are of materials particularly suitable for the functions .which they are designed to perform.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accolnpanying drawings, wherein a preferred form of embodiment of the invention is clearly shown.

In the drawings:

Fig. 1 is a verticalsection through a completed cylinder' embodying the invention.

Fig. 2 is a plan view'of the same with parts omitted.

Fig. 3 is a vertical lsection through the head portion of a modified form. y

Fig. 4 shows in vertical section a mold with the tube lin place ready for casting and also indicates a method ,of preheating the tube.

Fig. 5 is a section of a modified form of cylinder. A.

The drawings show a cylinder formed 'from a steel'tube 10, having a head 11 securely fixed therein, a base 12, and cooling elements or fins 13 secured to the upper portion. Such a cylinder is preferably made by spinning an inturned flange 20 upon a plain wrouvht steel tube of the proper length; settlngthe tube, upon a suitable spacing block 19, in a mold 21 with a suitable core 22, preferably made by ramming in sand filling the tube to within a short distance of the flange 20; and casting the head 11 preferably of copper inthe end of the tube in such fashion as to cover both sides of the flange and extend a short distance i above it and extend laterally su "'iciently tov be flush with the 10.

In making my improved cylinder, there is preferably formed in the mold, a short outer surface of the tube distance below ythe top of tube 10, a space- 25 for casting a ring of iron or other metal for the purpose of preheating tube 10 to a temperature suicient to insure a good After the mold has been thus prepared with the tube in place, the heating ring is poured in space 25 and then, after an interval of a few seconds, the. head metal. i

Suchy a procedure, insures a good bond between the metals and therefore 1an easy passage of heat from the one to the other in the operation of the finished cylinder.A

After the head casting has set the cylinder is taken from the mold and the base 12 andL fins 413 secured thereto.

. In securing the fins 13 to the cylinder use is made of the process described and claimed in application of Charles F. ,Kettering, Serial No. 514,014, filed November 9,1921.

Briefly, the process described in that application is as follows: After a rough finishing operation on the outside of the cylinder,

a thin coat of flux is applied and a sheet of'.

wired together andthe whole coated with a thick layer of flux. After drying, the assembly is heated under proper conditions to canse the brass to unite the copper fnning material to the ferrous metal cylinder.Y

After the operation of finning has been completed and while the assembly is still close. to the brazing temperature it may be put into a suitable quenching medium, such as oil, so as to give a very hard wearing surface on the interior of the cylinder barrel.

Before, after, or simultaneously vwith the finning operation the base 12 which may be a casting or forging, ma be secured to the cylinder `by brazing. r a suitable base may be welded in place-b some form of i the same time that the inning is accomplished. This is done by assembling the' cylinder base, brass and flux, in much the same manner asm the inmng and brazing i with the same heat.

` shown in The base may also be secured to the cylinder by electrically Welding them together and satisfactory cylinders have-been produced both ways.

After-or before the finning operation the valve ports 30 and 31 may be formed in the cylinder head and it is preferable to provide these with seats 32 and 33 by placing suitable 'seat material in proper location on core 22 and casting the head about them or such seats may be provided by brazing in suitable rings or other formed pieces, `before, after, or durin the fnning operation.

A modification o the above described cylinder pprlovided in the samel fashion, is

In this latter form a thin iron plate 4() is placed in the upper end of the tube 10 and the head? 11 cast as before so as to extend within the flange 20 and unite with both the steel and iron. This late 40 then furnishes the seats for the va ves in ports 30A and 31. The metals preferably chosen for the present p'ur se are steel for the tube or cylinder barre lcopper for the head proper, `cast iron for the inner plate 40, and 'cast or forged iron or steel for the base, but it should be understood that other metals might be substituted and some of the advantages of the present'structure retai-ned.

It is preferable but not necessarI to provide the tube with the flange 20.A xcellent results have been obtained by using the straight walls of the tube. to surroundthe cast in head and extend to the top thereof as shown in Fig. 5, or to extend not quite f to the top thereof allowing the head metal to extend over the upper edge and to the outer periphery of the tube.

Further, it is contemplated to use in the production of these cylinders7 a tube formed from a plate of steel, or other suitable wear resisting metal having a high tensile strength, rolled up to tube form and welded. It is also possible to use for this purpose a tube made by piercing an ingot and forming therefrom a cylinder having walls of sufficient dimensions and uniformity.

It will thus be seen that, instead -of the lusual form of cylinder wherein one metal is used to performvthe several functions of resisting wear,l furnishing strength and rigidity, conducting heat, etc., a cylinder is produced'which has in each portion a material particularly suitable for the function of that ortion. In the barrel, the propertiesof igh tensile strength and wear resistance are present; in the head, high heat conductivity; in the cooling fins, large area andhigh heat conductivity; and in the base great rigidity and machinability.`

What I claim4 is as follows-z 1. An 4internal combustion engine cylinder comprising a plain wrought metal tube constitutingl t e barrel of the cylinder, a head bonded integrally to one end ofthe tube and a base flange bonded to the otherA end of the tube'.

2. An internal combustion engine cyllnder comprising a plain wrought steel tube having an inturned flange at one end, and a cast metal head in which the inturned flange isl embedded and which is integrally Abonded to the head so that an uninterrupted metallic path is provided for the transfer of heat from the head to the steel tube. f

In testimony whereof I hereto aix my signature. e

FRANK o. CLEMENTS. 

